Measuring instrument



c. F. L AR'SON.

MEASURING INSTRUMENT.

APPLICATION FILED MAY 11, I917.

a SHEETSQSHEET I- 1,333,926, Patented Mar; 16,1920.

j amt 9 534m c. F. LARSON. MEASURING INSTRUMENT.

APPLICATION FILED MAY-II, I9]?- 1,333,926. Patented Mar.16,1920.

3 SHEETS-SHEET 2.

C. F LARSON.

MEASURING INSTRUMENT.

APPHCATION HLED MAY 11, 1917.

Patented Mar. .16, 1920.

3 SHEETSSHEET 3.

J7 @Qm til CARL F. LARSON, OF CHICAGO, ILLINOIS.

MEASURING INSTRUMENT.

, Specification of Letters Patent.

Patented Mai-.16, 1920.

Application filed May 11, 1917. Serial No. 157,851.

1 0 aZZ whom it may concern:

Be it known that L'CARLVF. LARsoN, a subject of the King of Sweden, andresident of Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful. Improvements in Measuring instruments,of which the following is a spcc1- fication.

My invention has reference to improvements in the class of measuringinstruments or weighing scales comprising a movable lever or arm havingpivots supported upon movable members upon which such pivots roll, thelever or arm being connected with a platform or other means adapted toreceive the articles to be weighed, inclicating means being operated byor from such lever or arm. The best weighing results are obtained whenthe aforesaid movable members maintain a proper or an approximatelydefinite relation to the pivots thereon, and are not obstructed in theirrocking movements under the pivots during weighing. There is a liabilitythat such members will be displaced from their proper operating relationto their pivots by reason of shocks or jars to which the scales areliable to be subjected, or by creeping or skidding, of such parts. Theleading object of my invention is to provide simple and eflicient meansthat-will permit such movable members to freely move by reason of therolling of said pivots thereon and-yet will serve to restore suchmembers to their proper relations with respect to said pivots, upon thereturn of the lever or arm to the normal or zero position, in casesuchmemhers have been displaced from such position.

A further object of my invention is to provide stops spaced from suchmovable members in their zero or normal positions and adapted to limitundue movement of such members with respect to the pivots thereon,whereby to assure that suchmembers cannot move too far from their properpositions respecting such pivots. certain of which stops may be utilizedin the restoration of the members to their proper positions after aweighing'operation, in case they have been displaced therefrom.

In carrying out my invention I provide in a measuring instrument havingmovable members and pivots supporting movable le ers or arms thereon,means connected with the pivots permitting the latter to rotate at alltimesfree'ly with respect to said members for the weighing operations,and adapted to cooperate with said members to restore them to theirproper positions upon the return of the levers or arms to the zeroposition incase a member has been displaced from its proper positionwith respect to the pivot thereon, whereby to assure for each weighingoperation aproper relation of such movable members to the correspondingpivots.

In the embodiment of my invention illustrated in the accompanyingdrawings I provide a projection upon each pivot for a correspondingmovable member adapted to cooperate withthe latter in case it has beendisplaced from its proper relation to the pivot to restore the member tosuch position upon the return of the corresponding lever to zero, suchprojection moving relatively to such member without resisting orcontrolling the same when the lever or arm is moved during a weighingoperation. I also provide a stop for each member located in suchposition that the aforesaid projection may .move the correspondingmember. into engagement with such stop substantially at the limit of thereturn stroke of the lever from .a weighing operation to assure theproper accurate restoration of the corre sponding member to the properposition in case such member may have moved from such position by reasonof shocks or jars, or creeping of the member with respect to thecorresponding pivot, or for other causes.

My invention further comprises novel d tails of improvement andcombinations of parts that will be more fully hereinafter set fo th andthen pointed out in the claims.

Reference is to be had to the accompanying drawings forming part hereof,wherein.

Figure 1 is a front elevation of a weighing mechanism embodying myinvention,

illustrating a dial and indicator or pointer partlvbrolren away; Fig. 2is an enlarged detail partlv sectional view of parts shown in Fig. 1.illustrating the movable parts in an operated position; Fig. 3 is adetail of part of Fig. 2 illustrating the parts in'the zero position;Fig. i is a side elevation of Fig. 2, partly in sectionqFig. 5 is adetail side view illustrating a modification. and Fig. 6 is 'a sectionon the line 6, 6, in Fig. Similar numerals of reference indicatecorresponding parts in the several views.

At 1 is indicated a support for the weighingmechanism, which maycomprise a standard or upright extending from a weighing platform, towhich latter a dr ft rod 2 may be connected in any well known manner. At3 is a casing adapted to inclose the weighing mechanism and at A is asuitable dial which may be connected-with said casing in any well knownmanner. A suitable frame is indicated at 4, shown secured upon support 1by screws 5, which frame supports the operating devices. At 6 are leversor weighted arms provided at opposite sides with pivots or gudgeons 7adapted to be supported by and to roll on movable members 8. Saidmembers 8 may be supported to rockin any suitable manner, and as a.means to delicately support said members I have shown knife edges 9received in V-like recesses 10 of the members 8, whereby the membersrest upon the knife edges. The knife edges are shown set in recesses ein frame t and secured in place by screws n. In the example illustratedthe sharpened ends of the knife edges 9 and the apices of the recesses10 are so located that planes passing therethrough coincide at the axesof the corresponding pivot 7 of lever 63, whereby the weight of and thatimposed upon lever 6 is transmitted to the corresponding members 8 andthe knife edgesalong or in the direction of such planes from the pointson the peripheries of the pivots or gudgeons where they touch theperipheries of the corresponding members 8 in such planes, wherebydirect thrusts of the weight are imposed through. members 8 upon theknife edges in any position of said members. The arrangement provides adelicate and positive support to enable the members 8 to rock oroscillate with a minimum of friction in either direction of movement ofthe members as caused by the rotation of the pivots or gudgeons incontact therewith,

in varying positions in which the levers may be tilted by reason of theload upon the platform or scale pan through the scale mecha nismconnected with the lever. The arrangement described affords advantage ofprotection against accumulation of dust and other foreign matter betweenthe members and their supports which would have a tendency to detractfrom the accuracy of the action of the scale mechanism. The arrangementis also superior to the supporting of mov able members upon ordinaryannular bearings, whereby to avoid accumulation of dust, foreignsubstances and oil on the movable supporting; parts which would have atendency to detract from the accuracy of the scale. My presentimprovements, however, are not limited to the support of the movablemembers for the pivots of the levers in manner set forth in cases whereother means of supporting such levers may be found desirable.

The surfaces 8 of members 8 are suitably curved to permit the readyrolling of the pivots 7. thereon, whereby the members 8 may rock as thelevers are operated. There may be one or more levers or weighted arms 6in the weighing mechanism, and a description of one and partscooperative therewith will apply toboth. The lever 6 may be operated orrocked during a weighing operation by any suitable means con necting thesame with the scale platform, pan or the like. I have illustrated thelever 6 having a curved upper portion 6 to which a flexible band orconnection ,11 may be attached by any suitable means, such as by a block12 and screw 13, securing such band to the lever, whence the banddepends over the curved surface 6* of the lever and is connected to thedraft rod 2 by any suitable means, such as by loop 1 L which may beclamped to the band by means of a block 15 and screws 16 in a well knownmanner. Where two spaced levers 6 are used in the weighing mechanismcorresponding bands 11 depending from said levers" may be clamped to theloop is by block 15 and screws 16, as illustrated in Fig. The members 8are shown arranged in pairs in overlapping relation for each i t 7, andtwo of such pairs of 1116111138135 are in spaced relation to support thepivots 7 on opposite sides of lever 6, as illustrated 1 in Fig. 4:. Itis desirable to maintain the members 8 in proper relation to thecorresponding pivot 7, to provide for proper and free rotation of saidpivots, and to permit the members to rock or move freely under thepivots without restriction during the weighing operation. In case themembers 8 should be displaced from such proper relation to the pivots 7,as by reason of shocks or are to which the scale inechanism may besubjected, or by reason of creeping or skidding of the members withrespect to the corresponding pivot 7 or vice versa, resistance to theproper or free rotation of pivots upon. the members may occur, tendingto inaccuracy in the indication of the weight of the article beingweighed. In accordance with my improvements 1 provide means to restore amem her 8 to its proper relation to the pivot 7 1..

at the termination of each weighing operation, in case such member mayhave be come displaced from such position, so that each time a weighingoperation commences the members 8Ywill be in their proper positions forweighing. For such purpose I provide the pivots 7 with projections orfingers 17, 18 that extend from each pivot 7 in position to cooperatewith a corre sponding member 8 upon the return of a lever 6 to zero froma welghmg positlon, to push or move such merrber 8 back to its properposition with relation to pivot 7 in case such member may have been displaced therefrom. The pro]ect-1ons 17, 18

are shown secured in proper positions upon pivots 7 by means of screws19, passing through the projections and threaded in the pivots. In Figs.1, 2, 3 and althe projections 17, 18 are shown located on the side ofthe corresponding pivot 7 such as to move in the direction away frommembers 8 when the latter are rocked by the pivots 7, as the levers 6swing at their lower ends outwardly during the weighing operation, as byturning in the direction of the arrows in Fig. 2. In case a member 8 maybecome displaced from its proper relation. to pivot 7 in the directionof fingers 17 or 18, the latter, upon the stroke of the correspondinglever 6 returning from the weighing position, will engage such memberand will push it under the pivot back to its proper position withrelation thereto. I provide back stops for said members indicated at 20,adapted to be engaged by the corresponding member 8 when it is pushed bya finger 17 or 18 at or back of the zero position of the correspondinglever 6. I have shown the stops 20 as adjustable toward and from thecorresponding members 8, said stops being illustrated in the form ofscrews adjustably carried by supports or arms 21 secured to frame 4 byscrews. At 22 are stops on thesides of the corresponding members 8opposite the respective stops 20, and spacedin suitable position wherebythe members may have suitable rocking movement between opposing stops 20and 22. The stops 22 are shown in the form of screws adjustably carriedby supports or arms 23 that are secured upon frame 1 by screws. -VVhenthe parts are in the zero position, such as illustrated in Figs. 1 and3, the projections 17. 18 may be in close juxtaposition with relation tothe corres onding member 8, which then may be sli htlv out of contactwith the associate back stop 20. and the stops 22 will be set in suchposition as to permit the desired freedom of movement of the members 8toward such stops when operated by the rotation of the orrespondinpivots 7 during the weighing action. When weight is placed upon thescale platform or pan, and the draft rod is pulled down thereby causingthe lever or arm 6 to swing outwardlv from frame 4, substantially asindicated in Fig. 2, the members 8 will be rocked by the correspondingpivots 7 then rotating in the direction of the arrows in Figs. 2,whereby the members 8 will "be moved away from the stops 20 and towardthe stops 22, the fingers 1'7 and 18 correspondingly moved away from themembers 8 (due to the difference in radius from the axes of pivots 7 tothe operating projections 17. 18 as compared to the radius ofmembers 8from their pivotal points on the knife edges 'to their curvedperipheries 8-), so as proper position, say toward the correspond- -1ngstop 22, by reason of shocks, ars, creeping or skidding of a memberwithrelation to its pivot, or for other reason, then upon return of thecorresponding lever 6 toward a zero position the projection 17 or 18 forsuch member will engage or coact with the latter as such finger returnsto the zero posi tion and will push such member under its pivot 7 toassure the restoration of such member to its proper position when theparts are again at zero. In other words, the projection 17 or 18 bycoaction with the then advanced member 8 will move the latter relativelyto the corresponding pivot 7 regardless of or additional to the movementof such member by rotation of pivot 7 thereon. By preference the stop 20and the corresponding projection 17 or 18 will be in such spacedrelation when the parts are at zero that the member 8 therebetween wlllbe slightly out of contact with such stop and projection (Fig. 3). lVhena lever 6 returns to Zero it will pass behind its zero position for ashort distance a ainst a sto I), such as against the frame a as at 4(Fig. 1), whereby the projections 17 and 18 may push the members 8 intoengagement with the corresponding stops 20, to assure-the properposition of said members for the next weighing operation, and when thelevers 6 are relieved of their momentum 111 such directlon, and returnto their balanced normal or zero positions, the fingers 17, 18 willbe'correspondingly moved in the direction away from stops 20 and themembers 8 will correspond ingly be moved by the pivots 7. If a mem her 8should have been displaced from its proper relation to pivot 7 in adirection toward stop 20, thenwhen the corresponding lever6 swings backtoward. zero from a weighing operation, the member 8 will encounter andbe stopped by its stop 20 and the pivot 7 r the lever beingstopped at 4whereby the proper relation of the memberto the pivot will be restoredfor the next weighingv operation. The stops 22 may be set in such aposition as to be quite near to the members 8 when the latter have beenmovedby the corresponding pivots 7 to their limit during a weighingoperation for the full capacity of the scale, whereby if a member shouldmore :under its' i oti the di ectian o step will rotate or skid on suchmember, 1

an ordinary manner.

22, as by reason of shocks, jars, creeping or otherwise, such movementof said member will be stopped by stop 22, whereby projection 17 or 18may engage such member on the return stroke of the corresponding lever 6toward zero, to restore said member to its proper-position in mannerbefore de scribed. I

Any suitable means may be provided to cause indication of the weightot-articles being weighed. I have shown a pointer 25 adapted to sweepover dial A in an ordinary manner, which pointer is secured to a shaft26 shown journaled upo' anti-friction rollers 27 journaled in bearingsupon frame at, in Said shaft is shown provided with a pinion in meshwith a rack 29 carried by an arm 30 pivot-ally supported at 31, on anupright 31 from frame 1. Means are interposed between one of the levers6 and arm 30 for roe-kin the lat ter and the rack to rotate the pointeror indicator. I have shown arm provided with an extension 30 carrying acam member 32 that is cooperative with an arm extending from a lever 6,an anti-friction roller or projection at 34 carried by said arm beingpreferably operative in the slot 32 oi cam member 32. The cam member hasslots 36 receiving bolts or screws 37 whereby the cam member may beadjusted relatively to arm 33 as required. The arrangement is such thatwhen lever 6 swings upwardly the arm 33 will operate the cam member 32to car e operation of arm 30 and rack 29 tor rot: ing the pointer orindicator 25 to indicate the weight of the article being weighed, thepointer or indicator being restored to Zero when lever 6 returns tozero.

My improvements provide a simple and eiiicient means to assure theproper position of the members 8 with relation to the correspondingpivots 7 for the comm cement of each weighing operation .vithout the interposition between such. members and pivots of any devices thatwouldhave a tend ency to resist the free movement oi members 8 by the roll ngof pivots 7 thereon during the weighing operation, and yet ailtordingmeans to assure the proper positions of said members when the parts areat zero for the commencement of a weighing operation, accomplishedduring; the return of the parts to zero.

In the modification illustrated in Figs. 5 and 6 the projections 17, 18are adapted to engage projections 8 carried by the members 8 and shz'extending from the sides thereof, instead of directly engaging themembers 8 on their side edges or in the plane thereof, as illustrated inthe other figures of the drawings. The projections 8 may be providedwith anti-friction rollers 8" for engagement with the projections 17, 18to reduce friction. In the form. shownin Figs.

6 and 7 the inner edges 1?, 18 of the projections 17, 18 are shownsuitably curved, as in cam-like form, with respect to the axes of pivot7 for the purpose of closely followin the movements of members 8notWith-.

standing the difference in radius of pivot 7 with respect to the radiusof member 8, whereby the projections 17, 18 will retain proper coactiverelation to the projections 8 of member 8 in all positions of said partsduring operation;

While I have illustrated and described a practical embodiment of myinvention, it will be understood that my invention is not limited to thedetails of construction and relative arrangement oi parts set forth.since the same may be varied, within the scope oi? the appended claims,without departing from the spirit of the invention.

Having now described my invention What I claim is 1. A measuring'instrument comprising a lever having; pivots, movable members adapt edto support said pivots, means movably supporting said members, and meanscoop erative between said members and pivots permitting; the members tobe moved by the pivots freely and unobstructed in one direction andcausing); said members to be restored. to proper relation to the pivotswhen moved in another direction.

2. A measuring instrument comprisinga lever having; pivots, movablemembers adapted to support said pivots, means movably SL'LDOOItiIlQ'said members back stops to'limit a J l movement oi. said members in onedirection, means cooperative between said members and pivots permittingthe members to be moved by the pivots freely and unobstructed away fromsaid stops causing said members to be restored to proper relation to thepivots when moved in the reverse direction and to engage said stops.

3. A measuring insnument comprising a lever having pivots, movablemembersadapted to support said pivots, means movably supporting saidmembers, back stops to limit movement of said members in one direction,means cooperative between said members and pivots permitting the membersto be moved by the pivots freely and unobstructed away from said stopsand causing said members to "be restored'to proper relation to thepivots when moved in the reverse direction and" to engage said stops,and stops on the sides of said members opposite the saidbach-stops tolimit movement of the members in the weighing; direction;

4. A measuring instrument comprising a l ver having; pivots, movablemembers adapted to support said pivots, means movably supporting saidmembers, and projections connected with said pivots and cooperative withsaid members to restore said members to proper relation to the pivots incase the members have been displaced therefrom when moving in onedirection and movable free from said members when moving in anotherdirection to permit the members to be moved by the pivots in suchdirection unobstructed by such projections.

5. A measuring instrument comprising alever having pivots, movablemembers adapted to support said pivots, means for n10vably supportingsaid members, and projections connected with said pivots to cooperatewith said members and located in position to move away from but in thedirection of movement of said members during a weighing operationWithout restricting the movement of said members and to move toward andcooperate with said members when moved from the weighing position torestore said members to proper position with relation to the pivot-s incase the members have been displaced from such position.

6. A measuring instrument comprising a lever having pivots, movablemembers adapted to support said pivots, means for movably supportingsaid members, and projections connected with said members to cooperate.

with said members and located in position to move away from but in thedirection of movement of said members during a weighing operationwithout restricting the movement of said members and to move toward andcooperate with said members when moved from the weighing position, torestore said members to proper position with relation to the pivots incase the members have been displaced from such position, and stopscooperative with said members when they have reached or have moved backof the zero position.

7. A measuring instrument comprising a lever having pivots, movablemembers adapted to support said pivots, means for movably supportingsaid members, and projections connected with said members to cooperatewith said members and located in position to move away from but inthedirection of movement of said members during a weighing operationwithout restricting movement of said members and to move toward andcooperate with said members when moved from the weighing position torestore said members to proper position with relation to the pivots incase the mem here have been displaced from such position, stopscooperative with said members when they have reached or have moved backof the zero position, and stops on the sides of said members oppositethe first named stops to limit movement of the members in the weighingdirection.

8. A measuring instrument comprising a lever having pivots on oppositesides, spaced movable members for each pivot, means movably supportingsaid members, and spaced projections carried by each pivot to cooperatewith a corresponding movable member, said projections being in positionto permit the members to move freely without obstruction by saidprojections during weighing and to engage said members to restore themto proper positions relatively to the pivots in case the members havebeen displaced therefrom.

9. A measuring instrument comprising a lever having pivots on oppositesides, spaced movable members for each pivot, means.

projections.

10. A measuring instrument comprising a lever having pivots on oppositesides, spaced movable members for each pivot, means movably supportingsaid members, and means cooperative between said members and pivotspermitting the members to be moved by the pivots 'freely andunobstructed in one direction and causing said members to be restored toproper relation to the pivots when moved in another direction, andadjustable stops spaced on opposite sides of said members to limit theirmovements in opposite directions.

11. A measuring instrument comprising a lever having pivots on oppositesides, spaced movable members for each pivot, means movably supportingsaid members, means cooperative between said members and pivotspermitting the members to be moved by the pivots freely and unobstructedin one direction and causing said members to be restored to properrelation to the pivots when moved in another direction, and arms spacedon opposite sides of said members and provided with stops to limitmovement of said members in opposite directions.

'12. In a measuring instrument the com- .bination of a lever havingpivots, movable members supporting the pivots, means movably supportingthe members to rock, an indicator, an arm having a rack, a pinioncooperative with the rack for operating the indicator, a cam memberoperatively con nected with said arm, and means carried by the levercooperative with the cam member for operating the latter to actuate theindicator.

13. In a measuring instrument the combinationof a lever having pivots,movable members supporting the pivots, means movably supporting themembers to rock, an in dicator, an arm having a rack, a pinioncooperative with the rack for operating the indieator, said arm beingprovided with an (221- Signed at New York city, in the county tension, acam member, means adjustably of New York, and State of New York, th1sconnecting theeam member with said eX- 7th day of May, A. D. 1917.

tension, and an arm connected with said CARL F. LARSON. 5 lever andcooperatively with the cam 1116111- Vitnesses:

her for operating the rack to actuate the'in- T. F. BOURNE,

dicator. MARIE F. WAINRIGHT.

